A152169 Number of positions that are exactly n moves from the starting position in the 2 X 2 X 2 Rubik cube puzzle using only one-way quarter moves.

1, 3, 9, 27, 78, 216, 583, 1546, 4035, 10320, 25824, 62832, 146322, 321876, 635632, 988788, 958176, 450280, 66420, 1192

Offset: 0

Author

Alejandro Lorca (alejandro.lorca(AT)fdi.ucm.es), Nov 27 2008

Keywords

• fini
• full
• nonn

Comments

A half-turn is considered to be two moves. The one-way quarter move method has historically being disregarded because of the mechanics of the Rubik's cube. It fills still the complete configuration space with the minimum set of generators.

Crossrefs

Cf. A079761, A079762